Print Engineering: Screen Printing is unique among printing methods.

Screen Printing is unique among printing methods. It can vary from a printed medical circuit, to a 14 color simulated process masterpiece on a t-shirt, to a 100 screen fine art serigraph. While the print process is very similar, squeegee, mesh, ink, and substrate, it’s the art that we use to make the screen that is unique to the product being printed. Textile printing of all the print techniques encompasses many different types of art. From solid spot color, to 4/C process, to simulated process printing. The choices of mesh, emulsions, squeegee, press print sequence and press adjustments can be overwhelming. Even if a shop manages to find it’s own ‘recipe’ of mesh counts, emulsions and press controls, the way the print is engineered in the art department determines how well production will run and how well the design sells. Too often the hand off of art to production is not managed well. If the art department doesn’t know what works in production then profits will suffer. If print production doesn’t know how to communicate in art and RIP terminology to the artist and separator the prints may not achieve the quality of the original art. No matter how good the art department or production manager skills are, print engineering begins the moment artwork is received. Almost any t-shirt printer or ad specialty printer has been handed a business card or is sent the logo from an email signature when the customer is asked for artwork.

Rule #1: Business Cards and Web Logos are not acceptable forms of artwork for T-shirt separation. Recreating art is very expensive and time consuming, yet too many times an art file is provided that won’t work. For today’s apparel printing we need digital vector art, or a bitmap version that is twice the size of what is needed for the final print at a resolution of 150 dpi minimally. Or 300 dpi if it is to final size, especially if halftones are to be used in the print process where tonal transitions need to be smooth and dramatic in the final print. The more data in the art, the easier it is to use filters and separation techniques that yield good positives for your screens.

So let’s say the customer has provided art, at a decent resolution. To the customer this can be a photograph of the subject with a very busy background and they want to add their boat name. Is this really art work you can use? Well yes, but you will spend a ton of time in Photoshop trimming out the subject matter from the background as well as formatting it with type and playing with the layout. This is another area where the customer may think they have provided art when he really has just provided a component to make the final art. Customers like this can be shocked when they are told how much it will cost to create their concept before separations begin. Ignoring the amount of art labor to produce the job can eat up all the ports you might have been able to make.

It’s what you can’t see that’s important in screen making

It’s what you can’t see that matters.

Screen room personnel often fall into a repetitive cycle in screen making. Handling screens becomes a constant work pattern where little thought is given to the condition of the emulsion, the screen room, the exposure process, or the condition of their equipment and the presses. They are constantly in a production ‘pinch point’ where a finite amount of screens can be processed through their area. Between sampling needs, production, and replacement screens for any that have broken down in production, they often aren’t aware of anything but the need to line up the art and get another screen shot. They work at near capacity throughput for their system. Screens that are made in a hurry and rushed to production often look identical to any other screens. They are coated the same way, the exposure is the same time, the blockout and tape job are identical. One screen may last thousands of prints while one rushed to a press may breakdown in 300-500 prints. Same emulsion, same exposure time, same personnel yet some screens work well, some breakdown. The faster they go the more issues production has on press. So what is wrong with this picture? How can we change the process to make life easier for everyone in the shop, and with this process improve profits and company stability? The problem with the above scenario is this: the screen issues cannot be seen with the naked eye. It’s what we don’t see that causes most of the problems. So let’s look at areas that we find are often neglected in the screen room. Click here to continue reading the article: It’s What You Can’t See That’s Important

Murakami Pre-stretched Screens

Murakami’s Pre Stretched Screens with Smartmesh:

Screen mesh technology has come a long way from the 12xx multilament mesh days. For those too young to know what 12xx means; this was a typical mesh made of multiple threads that screen printers used before monolament polyester mesh was developed.

Monolament Polyester mesh has significant advantages in clean up and image dehazing but when it was first introduced the elongation of the thread was enough to render a screen useless on a tight registration print. Then along came low elongation monolament mesh and screen printing explored tight dot on dot registration and no trap overlap in the art. Recently Murakami introduced Smartmesh that improved not only elongation, but accumulated elongation that occurs when repeated print strokes can cause momentary elongation as the screen warms up to the print process. Murakami Smartmesh also developed balanced warp and weft threads so the screen stretches proportionally in both warp and weft during printing. The combination of better balanced threads in Smartmesh results in higher retained tensions that prolong the printable life cycle of the screen while providing better prints and production yields.

Higher retained tension from Murakami Smartmesh reduces the amount of labor needed on retensionable screens to keep them at working tensions, but the real benefit is apparent on stretch and glue frames where higher retained tensions yield a longer work life on a less expensive frame. However, the quality of the frame and the stretch method are often overlooked when purchasing stretch and glue frames or stretching them yourself. In the following sections we will explore why Murakami’s Pre Stretched Frames offer exceptional print quality and production value that overcomes some of the issues in stretching mesh yourself. Click here to continue reading the article: Pre Stretched Screens

Basic Screen Room Training

This month’s newsletter gets back to the basics of screen making. Spring is the start of the busy season in screen printing with new companies opening their doors and new employees that need to know how to make a screen. Not just any screen mind you, but a screen that will have few pinholes, produce sharp crisp art details, and avoid breakdown on press. So this month’s article is an A to Z look at the products and process to create a durable screen.

Part One – Screen Preparation1. Cleaning the screen prior to De-hazing – The first step in screen preparation is to analyze the mesh for ghosts of ink that show up from a previous print run. If the mesh is new you can skip to Step 2. But if your screen has a ghost image read on. Ghosts or fabric stains are caused by ink from the last print run. The ink can get caught in the ‘creases’ of the ‘mesh knuckle’ and is usually seen when dark inks are used. Ghosts can cause pinholes or show up in a solid print area on the next job since they can interfere with the ink transfer and leave a ghost in the print.

Preventing Screen Haze: The easiest way to minimize this issue is to clean the screens immediately after the print run. This includes plastisol as well as water base, discharge, or HSA inks. Cleaning screens while the inks are still wet will prevent ink from drying in the mesh knuckle creases. This is especially true of discharge, water base and HSA inks that can air dry. Once the ink has dried you will need a haze remover to clean mesh. Murakami’s SC-501, SC-505 and SC-507 are designed to clean the mesh well without chemically flashing the emulsion and making it hard to reclaim. Screen Openers, Acetone, MEK, and other hot solvent chemistries can lock in the emulsion and make reclaiming difficult. Murakami screen cleaners avoid locking in the emulsion which allows the reclaiming process to go easier.

For water base and discharge inks a 5 gallon bucket of warm water works well, for plastisol or other inks the cleaners above work well, with SC-507 designed for graphic and industrial inks as well as textile inks. When companies tell me they have no time to wash the screens after a job has finished on press I point out that screen reclaiming personnel will spend 2 to 3 times as much time cleaning the dried ink compared to a worker cleaning wet screens at the press. Typically all that needs to be done is to card out the inks and wash the image area. This practice makes ghost removal in the reclaiming area an occasional job rather than needing to do it on all screens which wastes chemistry and labor.

2.Reclaiming the Screen: Dip tanks help save emulsion remover and soften the emulsion for reclaiming. Murakami ER-605 or ER-660can be used in the dip tank. For hardened screens ER-605 can be mixed 15:1 Always reclaim the screens before the emulsion remover can dry on the screen. If you apply emulsion remover and allow it to dry, it may be impossible to reclaim since emulsion remover can lock in the emulsion once it has dried on the stencil.

3. De-hazing: The residual image left by the previous print job can be difficult to remove once the ink has dried in the screen. If left in the mesh it can affect the appearance of the next print run. Discharge prints may not show anything when the ink is wet, yet when cured this previous print image will appear within a solid area of the print when cured. Process and Simulated Process jobs can also be affected. Add to this an increased risk of pinholes and break down in the ghost area and it is clear the screen is better off with the ghost image removed.

HR-701 is a non-caustic haze remover, a safer haze remover if you will. It needs to be used as soon as possible after the job has been broken down and the screen reclaimed. It can be applied and left on the screen for 10-15 minutes, then rinsed, prior to using a pressure washer to remove the ghost image. It works better on softer ghost images where the ink has not completely dried.

Murakami emulsion is engineered to accept complete exposure and still develop extremely fine details. If your emulsion cannot hold details at full exposure then that is a competitor’s product issue. Under exposing to get details will not yield a durable screen. This is a main difference found in Murakami emulsions. Expose them completely, no under exposure needed for details. Click here to continue reading the article: Basic Screen Room Training

Murakami LED Emulsions

The emulsions above can be exposed well on LED exposure units. Excellent resolution and durability. For additional technical information please call: 1.800.562.3534

Expose the Quality

Basic Screen Room Training

This month’s newsletter gets back to the basics of screen making. Spring is the start of the busy season in screen printing with new companies opening their doors and new employees that need to know how to make a screen. Not just any screen mind you, but a screen that will have few pinholes, produce sharp crisp art details, and avoid breakdown on press. So this month’s article is an A to Z look at the products and process to create a durable screen.

Part One – Screen Preparation1. Cleaning the screen prior to De-hazing – The first step in screen preparation is to analyze the mesh for ghosts of ink that show up from a previous print run. If the mesh is new you can skip to Step 2. But if your screen has a ghost image read on. Ghosts or fabric stains are caused by ink from the last print run. The ink can get caught in the ‘creases’ of the ‘mesh knuckle’ and is usually seen when dark inks are used. Ghosts can cause pinholes or show up in a solid print area on the next job since they can interfere with the ink transfer and leave a ghost in the print.

Preventing Screen Haze: The easiest way to minimize this issue is to clean the screens immediately after the print run. This includes plastisol as well as water base, discharge, or HSA inks. Cleaning screens while the inks are still wet will prevent ink from drying in the mesh knuckle creases. This is especially true of discharge, water base and HSA inks that can air dry. Once the ink has dried you will need a haze remover to clean mesh. Murakami’s SC-501, SC-505 and SC-507 are designed to clean the mesh well without chemically flashing the emulsion and making it hard to reclaim. Screen Openers, Acetone, MEK, and other hot solvent chemistries can lock in the emulsion and make reclaiming difficult. Murakami screen cleaners avoid locking in the emulsion which allows the reclaiming process to go easier.

For water base and discharge inks a 5 gallon bucket of warm water works well, for plastisol or other inks the cleaners above work well, with SC-507 designed for graphic and industrial inks as well as textile inks. When companies tell me they have no time to wash the screens after a job has finished on press I point out that screen reclaiming personnel will spend 2 to 3 times as much time cleaning the dried ink compared to a worker cleaning wet screens at the press. Typically all that needs to be done is to card out the inks and wash the image area. This practice makes ghost removal in the reclaiming area an occasional job rather than needing to do it on all screens which wastes chemistry and labor.

2.Reclaiming the Screen: Dip tanks help save emulsion remover and soften the emulsion for reclaiming. Murakami ER-605 or ER-660can be used in the dip tank. For hardened screens ER-605 can be mixed 15:1 Always reclaim the screens before the emulsion remover can dry on the screen. If you apply emulsion remover and allow it to dry, it may be impossible to reclaim since emulsion remover can lock in the emulsion once it has dried on the stencil.

3. De-hazing: The residual image left by the previous print job can be difficult to remove once the ink has dried in the screen. If left in the mesh it can affect the appearance of the next print run. Discharge prints may not show anything when the ink is wet, yet when cured this previous print image will appear within a solid area of the print when cured. Process and Simulated Process jobs can also be affected. Add to this an increased risk of pinholes and break down in the ghost area and it is clear the screen is better off with the ghost image removed.

HR-701 is a non-caustic haze remover, a safer haze remover if you will. It needs to be used as soon as possible after the job has been broken down and the screen reclaimed. It can be applied and left on the screen for 10-15 minutes, then rinsed, prior to using a pressure washer to remove the ghost image. It works better on softer ghost images where the ink has not completely dried.

Murakami emulsion is engineered to accept complete exposure and still develop extremely fine details. If your emulsion cannot hold details at full exposure then that is a competitor’s product issue. Under exposing to get details will not yield a durable screen. This is a main difference found in Murakami emulsions. Expose them completely, no under exposure needed for details. Click here to continue reading the article: Basic Screen Room Training

The Power of S Mesh

The Power of S Threads

Today’s screen printing world is in the midst of major change. PVC and Pthalate free inks are being used more and more, but they print far differently than any ink you have used in the past. Plastisol will still have its’ place, but many major clothing merchandisers want a safer ink for their product. This isn’t going to be like switching from one brand of plastisol to another. These inks require rethinking your print recipe of mesh and emulsion. From major athletic and licensed wear manufacturers to new children’s wear requirements these inks are here to stay. Migrating from plastisol to these new style of inks will require a dedication to learning how these inks cure, how to mix and maintain the inks during production and documenting the print recipe to determine best practices for success.

We’ve made the print part easy. We have been promoting S mesh for some time now with great results. The new PVC and Phthalate free inks benefit from the increased open area of Murakami S-mesh. With these meshes you can use less squeegee pressure and faster squeegee speeds to lay down less ink while still yielding great opaque prints. Faster squeegee speeds help these new inks to shear better. This low viscosity ink eliminates the need for a slow printing base plate common with plastisol inks and yields an extremely soft hand feel to the print. S Mesh from Murakami has one other significant advantage; print registration. Murakami’s S Mesh holds registration well. It has properties that aid in keeping your prints on press looking as good as when they were set up at the beginning of the print run.

Murakami Smartmesh retains excellent working tension. Mesh tension is often misunderstood. High mesh tension is not needed for water base, discharge or PVC/Pthalate free inks. These inks shear very easily with a good workable tension of 17-25 newtons. Whether you use stretch and glue or retensionable frames Murakami S mesh retains tension well.

Murakami T9

Murakami T9 – as seen at the ISS Show Long Beach 2018

Murakami T9 can print water base, discharge, plastisol, and high solid acrylic inks without the need for hardening. Fast Exposing, excellent resolution and durabililty provides a single emulsion for your stencils needs.

Murakami Technical Support has solutions for your screen department. We can help evaluate your current pre-press process to get the most out of your screen room. The solution to your stencil needs is just a phone call away;1.800.562.3534.

Expose the Quality

Publicación Reciente

Murakami Screen uses Smartmesh on all pre stretched and re-stretched screens. Smartmesh retains excellent working tensions for more jobs at optimum tension. Get longer life out of your stretch and glue frames with excelle... Read More ››

Murakami T9 – as seen at the ISS Show Long Beach 2018
Murakami T9 can print water base, discharge, plastisol, and high solid acrylic inks without the need for hardening. Fast Exposing, excellent resolution and dur... Read More ››